1. Field of the Invention
The invention relates generally to bristle brooms. In particular, the invention relates to angled-cut brooms wherein the sweeping surface of the bristles is generally oblique to the broom handle.
2. Description of the Prior Art
Angled-cut bristle brooms are generally well-known. They may be made of broom corn as shown in U.S. Pat. No. 246,500 (Hall) or of synthetic or vegetable fibers as shown in U.S. Pat. No. 4,250,589 (Alvin).
One of the main advantages of such brooms is that the sweeping surface formed by the ends of the broom bristles is oriented obliquely to the broom handle such that it bears uniformly against the floor along the whole length of the sweeping surface when the broom is in use. This not only enables all of the bristles to be evenly worn during use, but also facilitates sweeping corners and edges.
However, all known angled-cut brooms, as well as more traditional flat or straight-cut brooms whose sweeping surfaces are perpendicular to the broom handle, have bristles of uniform stiffness. In straight-cut brooms this inherent characteristic results in no differentiation between the sweeping ability of the broom tip (farthest from the user) or the rear end of the broom sweeping surface closest to the user, assuming, of course, that the straight-cut broom is used so as to have the entire sweeping surface bear evenly against the surface being swept. If the bristles are of uniform stiffness and relatively flexible or soft in order to be suitable for flat floor surfaces, the softness inhibits sweeping efficiency in corners and edges. Conversely, if the bristles are of uniform stiffness and relatively inflexible or hard enough to sweep corners and edges well, the broom would be inefficient for flat surfaces.
In known angled-cut brooms the use of bristles having uniform stiffness results in different considerations. For any given bristle stiffness, shorter bristles are stiffer and less flexible than longer bristles. Thus, in known angled-cut brooms having bristles of uniform stiffness and progressively increasing lengths, the tip of the broom is more flexible than the rear of the broom. Consequently, in sweeping floor edges or corners where dirt tends to accumulate, even the use of known angled-cut brooms is not particularly advantageous. There is, therefore, a need to overcome the deficiencies of the prior art by producing a broom which can be efficiently used on flat surfaces as well as corners and edges.
It is known in the prior art to combine bristles of different stiffnesses in one broom or brush. U.S. Pat. No. 2,043,758 (Lay) discloses a push broom having a forward row of coarse bristles and a rear row of finer bristles, the sweeping surfaces of both sets of bristles being inclined to lay flat upon the floor as the broom is pushed forward in normal use. U.S. Pat. No. 4,037,369 (Campbell) discloses a rotary floor maintenance brush combining bristles of varying degrees of coarseness. U.S. Pat. No. 237,154 (Armstrong) discloses a dust brush having a center core of relatively stiff bristles surrounded by a softer outer part. U.S. Pat. No. 430,077 (Jenness) discloses an animal grooming brush having bristles of varying degrees of stiffness arranged in generally concentric elliptical patterns. However, none of the foregoing prior art discloses use of a combination of stiff and soft bristles in the unique manner of the invention.
In view of the foregoing, it is an object of this invention to provide a broom having a combination of bristles of varying stiffness to enable efficient sweeping of flat surfaces as well as corners and edges.
It is a further object of this invention to provide an angled-cut broom having an oblique sweeping surface, the bristles adjacent the tip of the sweeping surface being stiffer than the remaining bristles.